۱- Introduction

۲- Blockchain overview

۳- Research methodology

۴- Descriptive analysis

۵- Taxonomy of blockchain-based applications

۶- Open issues and future trends

References

Abstract

This work provides a systematic literature review of blockchain-based applications across multiple domains. The aim is to investigate the current state of blockchain technology and its applications and to highlight how specific characteristics of this disruptive technology can revolutionise “business-as-usual” practices. To this end, the theoretical underpinnings of numerous research papers published in high ranked scientific journals during the last decade, along with several reports from grey literature as a means of streamlining our assessment and capturing the continuously expanding blockchain domain, are included in this review. Based on a structured, systematic review and thematic content analysis of the discovered literature, we present a comprehensive classification of blockchain-enabled applications across diverse sectors such as supply chain, business, healthcare, IoT, privacy, and data management, and we establish key themes, trends and emerging areas for research. We also point to the shortcomings identified in the relevant literature, particularly limitations the blockchain technology presents and how these limitations spawn across different sectors and industries. Building on these findings, we identify various research gaps and future exploratory directions that are anticipated to be of significant value both for academics and practitioners.

Introduction

Almost a decade ago Satoshi Nakamoto, the unknown person/group behind Bitcoin, described how the blockchain technology, a distributed peer-to-peer linked-structure, could be used to solve the problem of maintaining the order of transactions and to avoid the double-spending problem [1]. Bitcoin orders transactions and groups them in a constrained-size structure named blocks sharing the same timestamp. The nodes of the network (miners) are responsible for linking the blocks to each other in chronological order, with every block containing the hash of the previous block to create a blockchain [2]. Thus, the blockchain structure manages to contain a robust and auditable registry of all transactions. Blockchains introduced serious disruptions to the traditional business processes since the applications and transactions, which needed centralised architectures or trusted third parties to verify them, can now operate in a decentralised way with the same level of certainty. The inherent characteristics of blockchain architecture and design provide properties like transparency, robustness, auditability, and security [3, 4]. A blockchain can be considered a distributed database that is organised as a list of ordered blocks, where the committed blocks are immutable. One can see that this is ideal in the banking sector as banks can cooperate under the same blockchain and push their customers’ transactions. This way, beyond transparency, blockchain facilitates transactions’ auditing. Companies invest in this technology as they see the potential of making their architectures decentralised and minimising their transaction costs as they become inherently safer, transparent and in some cases faster. Therefore, blockchains are not just a hype.